1. Field of the Invention
The present invention relates generally to unmanned aircraft and, more particularly to a hand-launchable unmanned aerial vehicle (UAV) carrying sensor instrumentation for terrain surveillance, in which the components of the UAV are easily assembled in the field, can absorb landing shocks, and can be disassembled so as to fit in a small size package.
2. Description of the Related Art
There is a need for a small size unmanned aerial vehicle (UAV) which is able to collect data from a sensor such as a television camera carried on board the UAV and transmit the collected data to be received by a ground receiver, as for example at the point of launch.
Such a UAV must be capable of being disassembled, transported in a small size container to the point of launch, then quickly reassembled and launched, for data retrieval. With known UAV designs, the assembly process is often slowed due to the nature of the component connection elements which are often difficult to align and which can appear to be connected properly when in fact, the components are slightly out of alignment.
Once in flight, conventional UAV wing designs in which the servos controlling the elevons are mounted on the fuselage often cause the UAV to oscillate, resulting in instability that can negatively impact the data gathering mission.
Further difficulties often arise when the UAV returns upon completion of a surveillance mission, in that the landing process frequently results in considerable damage to the airframe of the UAV. This damage typically results when one of the wings is caught or collides with a ground-based object, twisting the airframe and tearing the wings and/or fuselage. Damage to the UAV may also occur as a result of the abruptness of the landing which can be caused when the launching clip tunnels into a soft ground surface, acting like an anchor and causing the UAV to flip or tumble rather than skidding on its belly.
Therefore, a need exists for an UAV that is constructed to absorb or dissipate the impact of landing without sustaining damage to a degree that would prevent nearly immediate redeployment, i.e., reuse while still in the field. The UAV must also be readily assembled and disassembled, with positively connecting components that provide fast and foolproof connection in a mission environment using a minimum of tools and requiring minimal operator training. Finally, the UAV must be constructed to have a low “ground adhesion” characteristic to further reduce shock and to maintain a steady airframe skid orientation upon landing.